0-99 Decoder

This PCB takes a 7-bit binary input ABCDEFG and decodes the binary into two BCD characters (tens place and ones place). A is the MSB and G is the LSB of the binary input.

Pinout

Hardware

This PCB uses a custom-programmed ROM (27C256 OTP) to generate 8-bits of BCD for each binary number. Two 7447 chips are used to decode each segment on a two-digit common-anode display (MAN6410), one for each digit (tens/ones).

Schematic

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